Hair straightener



FIG. 1 is a rear perspective view of the hair straightener showing my new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a rear elevational view thereof;

FIG. 4 is a left side elevational view thereof;

FIG. 5 is a right side elevational view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof; and,

FIG. 8 is the perspective view, showing the hair straightener in use. 

CLAIM The ornamental design for a hair straightener, as shown and described. 